When you receive this event, the structure members are set as follows.

The type member is set to the event type constant name that uniquely identifies
it. For example, when the X server reports a GraphicsExpose event to a
client application, it sends an XGraphicsExposeEvent structure with the
type member set to GraphicsExpose. The display member is set to a pointer
to the display the event was read on. The send_event member is set to True
if the event came from a SendEvent protocol request. The serial member
is set from the serial number reported in the protocol but expanded from
the 16-bit least-significant bits to a full 32-bit value. The window member
is set to the window that is most useful to toolkit dispatchers.

The parent
member is set to the parent window. The window member is set to the window
whose size, position, border width, and/or stacking order is to be reconfigured.
The value_mask member indicates which components were specified in the
ConfigureWindow protocol request. The corresponding values are reported
as given in the request. The remaining values are filled in from the current
geometry of the window, except in the case of above (sibling) and detail
(stack-mode), which are reported as None and Above, respectively, if
they are not given in the request.